Chai Xiaodong, Sun Ziwen, Li Haishuang, Zhu Liangyi, Liu Xiaodan, Liu Yantao, Pei Fei, Chang Qing
Department of Pathology, Peking University Third Hospital, Beijing 100191, China.
Department of Pathology, Peking University School of Basic Medical Sciences, Beijing 100191, China.
Beijing Da Xue Xue Bao Yi Xue Ban. 2024 Jun 18;56(3):512-518. doi: 10.19723/j.issn.1671-167X.2024.03.019.
To investigate the characteristics of the CD8 T cells infiltration from the 4 subtypes in medulloblastoma (MB), to analyze the relationship between CD8 T cells infiltration and prognosis, to study the function of C-X-C motif chemokine ligand 11 (CXCL11) and its receptor in CD8 T cells infiltration into tumors and to explore the potential mechanism, and to provide the necessary clinicopathological basis for exploring the immunotherapy of MB.
In the study, 48 clinical MB samples (12 cases in each of 4 subtypes) were selected from the multiple medical center from 2012 to 2019. The transcriptomics analysis for the tumor of 48 clinical samples was conducted on the NanoString PanCancer IO360 Panel (NanoString Technologies). Immunohistochemistry (IHC) staining of formalin-fixed, paraffin-embedded sections from MB was carried out using CD8 primary antibody to analyze diffe-rential quantities of CD8 T cells in the MB four subtypes. Through bioinformatics analysis, the relationship between CD8T cells infiltration and prognosis of the patients and the expression differences of various chemokines in the different subtypes of MB were investigated. The expression of CXCR3 receptor on the surface of CD8T cells in MB was verified by double immunofluorescence staining, and the underlying molecular mechanism of CD8T cells infiltration into the tumor was explored.
The characteristic index of CD8T cells in the WNT subtype of MB was relatively high, suggesting that the number of CD8T cells in the WNT subtype was significantly higher than that in the other three subtypes, which was confirmed by CD8 immunohistochemical staining and Gene Expression Omnibus (GEO) database analysis by using R2 online data analysis platform. And the increase of CD8T cells infiltration was positively correlated with the patient survival. The expression level of CXCL11 in the WNT subtype MB was significantly higher than that of the other three subtypes. Immunofluorescence staining showed the presence of CXCL11 receptor, CXCR3, on the surface of CD8T cells, suggesting that the CD8T cells might be attracted to the MB microenvironment by CXCL11 through CXCR3.
The CD8T cells infiltrate more in the WNT subtype MB than other subtypes. The mechanism may be related to the activation of CXCL11-CXCR3 chemokine system, and the patients with more infiltration of CD8T cells in tumor have better prognosis. This finding may provide the necessary clinicopathological basis for the regulatory mechanism of CD8T cells infiltration in MB, and give a new potential therapeutic target for the future immunotherapy of MB.
探讨髓母细胞瘤（MB）4种亚型中CD8 T细胞浸润的特征，分析CD8 T细胞浸润与预后的关系，研究C-X-C基序趋化因子配体11（CXCL11）及其受体在CD8 T细胞浸润肿瘤中的作用及潜在机制，为探索MB的免疫治疗提供必要的临床病理依据。
本研究选取2012年至2019年多个医学中心的48例临床MB样本（4种亚型各12例）。对48例临床样本的肿瘤进行转录组学分析，采用NanoString PanCancer IO360 Panel（NanoString Technologies）。用CD8一抗对MB福尔马林固定、石蜡包埋切片进行免疫组织化学（IHC）染色，分析MB 4种亚型中CD8 T细胞的差异数量。通过生物信息学分析，研究CD8 T细胞浸润与患者预后的关系以及MB不同亚型中各种趋化因子的表达差异。通过双重免疫荧光染色验证MB中CD8 T细胞表面CXCR3受体的表达，探索CD8 T细胞浸润肿瘤的潜在分子机制。
MB的WNT亚型中CD8 T细胞的特征性指标相对较高，提示WNT亚型中CD8 T细胞数量显著高于其他3种亚型，这通过CD8免疫组化染色及使用R2在线数据分析平台进行的基因表达综合数据库（GEO）分析得以证实。并且CD8 T细胞浸润增加与患者生存呈正相关。WNT亚型MB中CXCL11的表达水平显著高于其他3种亚型。免疫荧光染色显示CD8 T细胞表面存在CXCL11受体CXCR3，提示CD8 T细胞可能通过CXCR3被CXCL11吸引至MB微环境。
WNT亚型MB中CD8 T细胞浸润多于其他亚型。其机制可能与CXCL11-CXCR3趋化因子系统的激活有关，肿瘤中CD8 T细胞浸润较多的患者预后较好。这一发现可能为MB中CD8 T细胞浸润的调控机制提供必要的临床病理依据，并为未来MB的免疫治疗提供新的潜在治疗靶点。
